Freescale Semiconductor Xtrinsic MAG3110 Magnetometer RD4247MAG3110 RD4247MAG3110 User Manual
Product codes
RD4247MAG3110
Advanced eCompass Features
RD4247MAG3110 Sensor Toolbox Tilt-Compensated eCompass Kit User’s Guide, Rev. 2
Freescale Semiconductor
13
Table 1 Configuration Frame
Screen frame
Description
Magnetometer
HAL
1
and Gain
Aligns the magnetometer package to the x, y,
and z axes of the evaluation board in multiples
of 90 degrees. Permitted values are -1, 0, and
1. The magnetometer reading used by the
eCompass algorithms is obtained by
multiplying the raw magnetometer
measurement by this three-by-three matrix.
and z axes of the evaluation board in multiples
of 90 degrees. Permitted values are -1, 0, and
1. The magnetometer reading used by the
eCompass algorithms is obtained by
multiplying the raw magnetometer
measurement by this three-by-three matrix.
These Hardware Abstraction Layer settings should be
changed only if the sensor toolbox software is being
used with a customer evaluation board whose sensor
package orientation does not match that of the
MAG3110 and MMA8451Q daughter board.
changed only if the sensor toolbox software is being
used with a customer evaluation board whose sensor
package orientation does not match that of the
MAG3110 and MMA8451Q daughter board.
Accelerometer
and Gain
Aligns the accelerometer package to the x, y,
and z axes of the evaluation board in multiples
of 90 degrees. Permitted values are -1, 0, and
1. The accelerometer reading used by the
eCompass algorithms is obtained by
multiplying the raw magnetometer
measurement by this three-by-three matrix.
and z axes of the evaluation board in multiples
of 90 degrees. Permitted values are -1, 0, and
1. The accelerometer reading used by the
eCompass algorithms is obtained by
multiplying the raw magnetometer
measurement by this three-by-three matrix.
Low-Pass Filters
The Angles LPF (samples) list-box field sets the 1/e time constant (in samples) of the single-pole,
exponential low-pass filters acting on the roll, pitch, and compass heading angles.
exponential low-pass filters acting on the roll, pitch, and compass heading angles.
The default setting is 16 samples which equates to 0.4s 1/e convergence at the default, 40-Hz sampling
frequency.
frequency.
Sampling Rate
Selects the magnetometer’s output data rates and over-sampling ratios.
The default rate is 40 Hz. For more details on these settings, see the MAG3110 3-Axis, Digital
Magnetometer Data Sheet (MAG3110).
Magnetometer Data Sheet (MAG3110).
Calibration
Settings
Enables configuration of four parameters used for magnetic calibration.
Smart FIFO
Configures the data structure that calibrates the device by storing measurements
of the geomagnetic field at different orientations.
of the geomagnetic field at different orientations.
The default setting is 3x Pitch times 6x Roll times 6x Yaw ranges to give a total of
108 entries. The alternative setting is 4x Pitch times 8x Roll times 8x Yaw values
for a total of 256 entries.
108 entries. The alternative setting is 4x Pitch times 8x Roll times 8x Yaw values
for a total of 256 entries.
Calibration Interval
Selects whether the calibration algorithms execute every 10, 20, 40, 80, 120, or
160 samples.
160 samples.
At the default sampling rate of 40 Hz, this corresponds to a calibration every 0.25,
0.5, 1, 2, 3, or 4 seconds.
0.5, 1, 2, 3, or 4 seconds.
Min Equations
Defines the minimum number of measurements stored in the Smart FIFO to be
used for calibration.
used for calibration.
The default setting is 16 measurements with the alternatives of 10, 12, and 14.
The lowest setting is 10 because it is impossible for the 10-element calibration
model to be solved when fewer than 10 measurement equations are available.
The lowest setting is 10 because it is impossible for the 10-element calibration
model to be solved when fewer than 10 measurement equations are available.
Max Equations
Defines the maximum number of measurements stored in the Smart FIFO to be
used for calibration.
used for calibration.
The default setting is 64, but this can be set as high as 256. Generally, more
measurements are better, but at the expense of increased processing and power
consumption.
measurements are better, but at the expense of increased processing and power
consumption.
If this field is set to 128, 192 or 256, the Smart FIFO field should be set to its larger
value because the smaller value contains only 108 entries which limits
measurements to that number.
value because the smaller value contains only 108 entries which limits
measurements to that number.
Reset
Resets the Configuration screen settings to default values.